Investigating the effect of IAA growth regulator on plant tissue

Name a suitable seed you used

Cress seed

Describe how you measured the effect of IAA on plant tissue

measure the length of root or shoot with ruler or grid

Where in plants are growth regulators produced

Meristem

How are growth regulators transported around a plant

Dffusion

What is a tropism

Growth of a plant in response to a stimulus

A growth regulator that promotes growth

Auxin

A growth regulator that inhibits growth

Ethene

Preparing different concentrations of IAA

• dissolve 100mg of IAA in a few ml of ethanol and bring it up to 1L with distilled water (stock solution)

• pipette 10 ml of the stock solution into the first tube

• using a syringe, take 1ml from tube 1 from tube 1 and to tube 2. add 9 ml of distilled water

• repeat until you get to tube 7

• tube 8 is the contol with 9 ml of distilled water

Growing seeds in different IAA concentrations

• fit a circular acetate grid on the base of each dish and place 6 radish seeds across the middle

• cover seeds with filter paper

• add 3ml from each tube to its matching dish

• place cotton wool over filter paper and pour remaining 6ml of each solution onto cotton wool

• seal dishes with tape

• leave in an incubator at 25deg celsius for 3 days

Results

IAA causes root and shoot elongation